// Copyright 2021 The Dawn & Tint Authors
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
//    contributors may be used to endorse or promote products derived from
//    this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "dawn/native/ScratchBuffer.h"

#include "dawn/native/Device.h"

namespace dawn::native {

ScratchBuffer::ScratchBuffer(DeviceBase* device, wgpu::BufferUsage usage)
    : mDevice(device), mUsage(usage) {}

ScratchBuffer::~ScratchBuffer() = default;

void ScratchBuffer::Reset() {
    mBuffer = nullptr;
}

MaybeError ScratchBuffer::EnsureCapacity(uint64_t capacity) {
    DAWN_ASSERT(capacity > 0);
    if (!mBuffer.Get() || mBuffer->GetSize() < capacity) {
        BufferDescriptor descriptor;
        descriptor.size = capacity;
        descriptor.usage = mUsage;
        DAWN_TRY_ASSIGN(mBuffer, mDevice->CreateBuffer(&descriptor));
        mBuffer->SetInitialized(true);
    }
    return {};
}

BufferBase* ScratchBuffer::GetBuffer() const {
    DAWN_ASSERT(mBuffer.Get() != nullptr);
    return mBuffer.Get();
}

}  // namespace dawn::native
